DENVER  Scientists have discovered that byproducts of such everyday activities as using anti-bacterial hand soap or zapping mosquitoes with bug spray are winding up in streams and groundwater from the Denver area to remote spots in the Colorado mountains.

Some of the chemicals documented in the U.S. Geological Survey released Wednesday are suspected of disrupting fish reproduction and increasing resistance to antibiotics. The compounds that are regulated were within limits deemed safe, but no standards exist for most of the 62 chemicals.

The study is intended as a starting point for more study of how dozens of chemicals are entering waterways and the potential impacts on people and the environment.

"There's the potential for the chemicals to enter (waterways) wherever there's human activity," said Lori Sprague, the report's co-author.

Bill Battaglin, the other author, said scientists expected to find chemicals associated with detergents, disinfectants and pesticides in urban waterways, but were surprised to find some of them in more remote areas.

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Fire retardants, caffeine, steroids, prescription drugs, insecticides and pesticides are also ending up in the water. Some of the compounds were found in rural water wells, although in fewer numbers and lower concentrations than in urban areas.

The statewide study was a spinoff of a national survey that concentrated on the Platte River in the Denver area.

"That prompted us to look around the whole state," Battaglin said.

Scientists analyzed 125 samples collected between October 2002 and September 2003.

The Colorado Department of Public Health and Environment is closely tracking the findings, said Mark Pifher, director of the water quality division. State and federal environmental officials and university researchers have been discussing the developing research on all the chemicals turning up in water.

"The ubiquitous nature of the chemicals was a bit surprising, but I guess nobody's looked that closely before," Pifher said.

Determining the potential long-term effects of the chemicals, their sources and figuring out how to reduce them, perhaps through more advanced wastewater treatment, likely would take several years and several million dollars, he added.

The chemical nonylphenol, a remnant of detergent and found in higher concentrations in urban areas, is known to disrupt fish reproduction and growth. Scientists suspect that chemicals from anti-bacterial disinfectants, found in hand and dish soaps, increase the resistance to bacteria.

"This is a starting point for further investigation," Sprague said. "The one message the public can take away is that everyday activities have the potential to affect the quality of life."